A substrate processing system for finely processing a semiconductor wafer (hereinafter simply referred to as “wafer”) includes, for example, a load port on which a FOUP (Front Opening Unified Pod) accommodating a plurality of wafers is mounted and a vacuum processing chamber which processes a wafer.
In the substrate processing system, the wafer is transferred from the FOUP mounted on the load port to the vacuum processing chamber via a load lock chamber and a transfer chamber (see, for example, Patent Document 1).
In recent years, from the viewpoint of improving the throughput, the number of process modules provided in a substrate processing system is increasing. In such a substrate processing system, different processes may be performed for each process module. As an example, each of the process modules may be associated with a wafer lot, and each of the process modules may process the wafers of only one corresponding lot. In this case, the wafers are not transported in order among the respective process modules, but are transported between one of the process modules and a load port. In this case, it is preferable that the number of load ports is equal to or more than the number of process modules. Therefore, in a substrate processing system having a large number of process modules, the number of load ports disposed in a loader module (a carrier transport device) increases.